Bryant T874 Thermostat User Manual


 
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
107 60-24858
Fig. 65. Schematic and hookup of T874A with Q674B. Used in standard applications.
Fig. 66. Schematic and hookup of T874A,D,F with Q674D. Used in standard applications.
C1
RISE
L1
(HOT)
L2
1
L1
(HOT)
L2
1
H1
FALL
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
M5976
C1
ANTICIPATOR
H1 ANTICIPATOR
SYSTEM
SWITCH
HEAT
OFF
COOL
FAN
SWITCH
AUTO
ON
NO. 1 HEAT RELAY
HEAT DAMPER
COOL DAMPER
FAN RELAY
NO. 1 COMP. RELAY
FILTER
LED (RED)
SERVICE LED
(YELLOW)
X2
X1
Y1
Y2
G
RC
RH
B
W2
W1
1
4
6
8
9
10
11
O
THERMOSTAT SUBBASE SYSTEM COMPONENTS
W2
W1
M7011
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
Y2
RH
RC
Y1
H1 ANTICIPATOR
H2 ANTICIPATOR
H1
FALL
FALL
H2
1
4
5
6
8
9
10
11
NO FAN
SWITCH
NO SYSTEM
SWITCH
L1
(HOT)
L2
1
L1
(HOT)
L2
1
HEAT RELAY 1
HEAT RELAY 2
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.